Thread trimming method



W. N. HADLEY THREAD TRIMMING METHOD June 1, 1965 2 Sheets-Sheet 1 Filed NOV. 21 1963 FIG.

FIG. 3

FIG.4

Y m D vH m N D E R F L W ATTORNEYS FIG. 5

United States Patent ice 3,186,057 THREAD TRlMMlNG METHUD Wilfred N. Hadley, Springfield, Vt., assignor to Hadley Company, Inc, Springfield, Vt, a corporation of Vermont Filed Nov. 21, 1963, Ser. No. 325,407 7 Claims. (Cl. 26-7) The present invention relates generally to the manufactureof textile goods and more particularly is directed toward a novel method for trimming extra length threads attached to a woven web.

In weaving griege goods long hanging threads frequently appear on the surface of the material between the selveges.

enever a warp thread breaks in the weaving process, the weaver has to splice the thread to draw it through the correct heddle and harness and then through the correct dent of the reed in order for the weaving to continue. The extra length of thread is left hanging on the top surface of the cloth as the weaving begins again and, since the weaver is usually occupied with up to 50 or more looms, he does not have time for this thread to weave in and then break the end off close to the cloth body. As a result, these threads are left hanging to the cloth and may be up to 2 feet or more in length.

These long hanging threads tend to cling closely to the surface of the fabric when traveling through various idler and draft rolls. So closely do the threads cling to the fabric that neither the induced suction from subsequent shearing operations or the action of the shearing blades themselves will pick up the free ends of the threads or any part of them to shear them off. This is especially true when the blades are dulled even slightly. Unless the spurious threads are trimmed off by hand, at considerable added expense, they cause light surface streaks on the fabric when it subsequently goes under finishing and printing operations. While various attempts have been made to remove these threads automatically, none of them has proven to be completely effective.

Accordingly, it is an object of the present invention to provide a new and improved method for automatically trimming loose hanging threads attached to a woven web.

Another object of this invention is to provide a novel, self-cleaning apparatus for trimming threads from woven sheet fabrics.

Still another object of this invention is to provide a novel mechanism for insuring that the proper surface of a woven fabric is fed to a trimming station.

More particularly this invention features a novel method for trimming relatively long threads which are attached by one end to a moving fabric web which method includes the steps of first arranging the threads so that the attached end of the thread leads the free end thereof. The threads are then brushed forwardly and outwardly of the web so that each thread is tensioned right-angularly with respect to the plane of the fabric. In this condition the threads are carried against a trimming blade to be severed. This invention also features a novel apparatus for snipping long hanging threads from a woven web and includes a rotary brush mounted across the moving web and adapted to be rotated in a direction opposite to the moving web for arranging all of the free hanging threads in the same direction. Spaced behind the first brush is a second rotary brush mounted across the moving web and adapted to be rotated in the same direction as the web and at a higher rate of speed. The second brush is characterized by spaced bristle or wire clothed sectors the leading edge of each sector being adapted to pick up a long hanging thread and tension it outwardly from the web while the thread is carried against a knife edge extending across the web behind the second brush and in proximity thereto.

3385,57 Patented June 1, 1965 In addition, this invention features a resiliently mounted roller positioned adjacent and unwinding cradle and operatively connected with the power system for advancing the web. The roller is so positioned that the web can be wrapped over the roller from only one feeding position. This will insure that the fabric is advanced to the machine with the propersurface exposed to the brushes and cutter.

But these and other features of the invention, along with further objects and advantages thereof, will become more fully apparent from the following detailed description of preferred embodiments thereof, with reference being made to the accompanying drawings in which:

' FIG. 1 is a view in perspective showing a thread trimming apparatus made according to the invention,

PEG. 2 is a view in side elevation of the FIG. 1 apparatus,

FIG. 3 is an end view ofa thread snagging brush employed in the invention,

FIG. 4 is a top plan view of a modified thread trimming apparatus,

FIG. 5 is an end view showing another modification of the invention,

FIG. 6 is a top plan cutting bar,

FIG. 7 is a view similar to FIG. 6 showing another modification of the cutting bar,

FIG. 8 is a view in end elevation showing a modified thread trimming installation,

FlG. 9 is a view in side elevation of an automatic feed stop mechanism, and

FIG. 10 is a schematic view of the feed control system ofFlG. 9. 1'

Referring now to the drawings, the reference character 1% generally indicates a woven web advancing in the direction of the arrow over a supporting surface 12. The web 10 has been illustrated in the condition that it comes from the loom. That is to say a number of relatively long threads 14 hang loosely by one end to theweb, the opposite end being free. Normally, these threads will be traveling with their free end in advance of the attached end although some may be oriented in the opposite direction. In any event, in order to arrange all of the threads in the same direction with the attached ends in advance of the free ends, a laying brush'16 extends across the web in tangential contact therewith.

The laying brush 16 is in the form of a roller having a cylindrical configuration and fabricated with a steel core having a solid perimeter covered with straight 1%" staple wire bristles, for example, which extend radially outward from the surface. The laying brush 16 is supported at its ends by bearings 18 and 2G and rotated in a clockwise direction by means of a motor 22, a belt 24- and a pulley26. It will be noted that the direction of rotation of the laying brush 16 is against the advance of the web 10 so that all of the threads 14 passing under the laying brush will be arranged so that their attached ends will be in advance of their free ends as shown at .28.

Mounted further along the supporting surface 12 is a snagging brush 30 spaced preferably at least 3 feet from the laying brush 16 and supported at its ends by bearings 32 and 34. The snagging brush is fabricated typically with a 6" diameter steel core 36 normally carrying four brush sectors 33 in evenly spaced relation about the cylin drical surface of the core.

In practice, the brush sectors 38 may be straight wire bristles as shown in FIGS. 1 and 2 or, preferably, the wires may be bent as suggested in FIG. 3 to insure that each and every one of the threads 14 will be snagged by the bristles. As indicated in FIG. 3, the individual bristles will be bent forwardly in the direction of rotation of the snagging brush 30. In any event the snagging brush is rotated counterclockwise in the direction of the cloth view showing a modified thread movement by means of a motor 40, a belt 42 and a pulley 44. The snagging brush is rotated at a speed in excess of the speed of the cloth which may be advancing at a rate of 200 to 240 yards per minute. In practice, a speed of about in excess of the cloth speed is desired for the snagging brush although this may be varied depending upon the character of the fabric.

The function of the snagging brush is to brush each of the threads 14 outwardly from the surface of the web 10 as they pass under the brush. As shown in FIG. 2 each thread, as it passes under the snagging brush, is pulled first forwardly and then outwardly from the fabric with the free end being carried around the snagging brush so that the thread is tensioned erect from the web. It will be understood that with the free end trailing the attached end of the thread and the snagging brush moving at a faster rate than the fabric, the attached end will pass under the brush whereas the bristles will then take hold of the free portion of the thread pulling it forwardly and around in a counter-clockwise direction as the attached end moves forwardly with the web. In this erect tensioned condition, the web carries the attached portion of the thread forwardly and against a cutting bar 46 to trim the thread near the surface of the Web.

The cutting bar will be seen to extend transversely across the width of the web and is supported at its ends by blocks 48 just above the surface of the fabric. The knife edge of the cutting bar extends in close proximity to the periphery of the snagging brush 30. In this position, the knife edge is adapted to sever each of the threads 14 that are picked up by the brush and carried against it in a tensioned erect condition.

In order to further enhance the ability of the snagging brush to pick up each of the loose hanging threads 14, the laying brush 16 may be mounted diagonally across the web 10 as suggested in FIG. 4. Typically, the laying brush may be arranged at a angle with respect to the moving web whereby each of the threads 14 passing under the laying brush will be brushed into a diagonal position on the web as indicated by the reference character 43 in FIG. 4. With the threads arranged in this fashion, the bristles of the snagging brush 30 will engage the threads more or less sideways rather than lengthwise thereby being more easily snagged by the bristles.

By forming the snagging brush 30 with a number of spaced bristle sectors 38, each sector presents a corner or leading edge which will also improve the ability of the brush to snag and pick up the threads passing under the brush. It will be appreciated that the segmented arrangement of the snagging brush will be more efiicient in picking up threads than would be the case if bristles covered the entire cylindrical surface of the core. Moreover, accumulated threads are easily removed from the brush by the operator stopping the snagging brush and cutting with a knife or scissors between a pair of sectors and then stripping off the threads.

While normally the extraneous threads 14 will appear only on the upper surface of the fabric, it may happen from time to time that some loose hanging threads will appear on the opposite side of the web by reason of the roll of fabric being placed backwards in an unwinding cradle. In order to insure that threads on both sides of the fabric are trimmed, the same thread snagging arrangement may be repeated on the opposite side of the fabric as suggested in FIG. 5. Thus a laying brush 16 will be placed on either side of the web as will be a snagging brush 30 and a cutting bar 46.

'In FIGS. 6 and 7 there are illustrated two modifications of the cutting bar. In the FIG. 6 embodiment, a cutting bar 52 is slidably supported between blocks 54 and connected to a suitable oscillating drive mechanism 56 whereby the bar may be driven back and forth as indicated by the arrows. It will be understood that for certain types of materials the oscillating cutting edge will provide a more efficient shearing action than a fixed cutting edge.

In the FIG. 7 embodiment a sickle bar is provided for trimming the threads. The sickle bar comprises a fixed cutting member 60 supported at its ends by blocks 62 and formed with a serrate leading edge 64. Mounted flush to the underside of the member 60 and slidably mounted in the blocks 62 is a second cutting member 66 also having a serrated leading edge 68. One end of the cutting member 66 is connected to a suitable oscillating drive mechanism 79 whereby the member 6-5 may be reciprocated back and forth to provide a positive cutting action for threads carried against the serrated edges.

Referring now more particularly to FIG. 8, there is illustrated a further modification of the invention and in this embodiment a thread trimming apparatus is mounted on a frame 72 which may be located between a scray and a shearing mechanism. Typically, the web It is roven over a tension roll 74 for regulating the cloth tension, thence under an idler roll 76 and over another idler roll 78. As the fabric moves vertically downward it passes first into contact with a diagonally mounted laying brush 80 which will arrange all of the loose hanging threads 82 into the same diagonal position. Approximately three feet or so below the laying brush 80 is located a snagging brush 84 which picks up the threads 82 in the manner previously described for trimming by the knife edge 86. The trimmed material is then carried down between a pair of guide rollers 88, under an idler roll to the shearing mechanism.

In the FIG. 8 embodiment, an automatic cleaning mechanism is provided for the snagging brush. Normally, after the thread is snipped by the knife edge 86, the severed thread will Wrap itself around the snagging brush and after a sutiicient amount has accumulated, it would normally be necessary to stop the machine and the operator would have to out along the core of the snagging brush between the brush sectors and thus peel off the accumulated threads. In order to eliminate this intermittent stopping of the machine a cleaning brush 92. is mounted to mesh with the outer periphery of the snagging brush 84 in order to pick off each of the severed threads 82 so that they may be carried away through a vacuum exhaust hood 94. The cleaning brush 92 typically is of a construction similar to the laying brush 80 having straight wire bristles and is rotated in a clockwise direction so that the cleaning and snagging brushes will mesh in the same direction to facilitate removal of the severed threads. In practice, the cleaning brush rotates faster than the snagging brush and is positioned above and slightly b hind the snagging brush. The points of the cleaning brush wires dip slightly into the sloping set wires of the snagging brush whereby they will strip the threads from the bent wires. The flexible characteristics of the wire will snap the severed threads into the exhaust hood )4 and out through to a collector. A housing 96 normally will enclose as far as possible the rotating cleaning brush.

Referring now more particularly to FIGS. 9 and 10, there is illustrated a safety mechanism for insuring that the proper surfaces of the fabric 10 always appears on the same side as it is advanced through the thread snipping station. As the cloth is woven on the loom, it is rolled up on a core 98. When the roll is fully wound it is transferred from the loom to an unwinding cradle 160 where the leading end is sewn to the trailing end of a preceding section of cloth and the joined pieces are carried through various finishing operations such as shearing and the like. The cradle 100, as shown in FIG. 9, is located below a railway sewing machine 102 which is adapted to traverse the fabric for joining the ends of two sections. In order to insure that the web 10 is unwound from the left-hand side of the roll so that the proper surface will be upward, a swinging idler roll 10 is mounted to a frame 106 by means of link arms 108. Springs 110 normally urge the idler roll 104 outwardly in a c0unterclockwise direction and away from a normally open switch 112 in circuit with a motor 114 which drives the cloth.

When the web is unwound from the left-hand side of the roll in the manner shown in FIG. 9, it will wrap over the idler roll 104 asit is carried up and around an idler roll 116. The weight of the fabric roll in conjunction with the tension applied to the fabric as it is advanced to the machine, will bias the roll N4 clockwise to close the switch 112 and thereby energize the motor 114. It will be noted that the idler roll 104 is located in such a position that if the cloth roll were placed in backwards so that the web were unwound from the right-hand side, the web would not pass over the idler roll 104 and the switch 112 would remain open preventing operation of the machine. Thus, it is necessary for the operator to place the cloth roll in the cradle with the proper side out.

This arrangement has several added advantages. First of all, when the roll of fabric reaches the end, the tension on the Web will be released causing the idler roll 104 to swing out and open the switch thus automatically stopping the motor and the advance of the cloth. The operator can then sew the end of the cloth to the leading edge of the next roll of cloth which will be placed in the cradle. The device thus serves as an automatic stop for the cloth when it becomes fully unwound. Secondly, there is no danger of the core flying out from the cradle when the roll is completely unwound. It has happened on various occasions that when a roll of cloth is placed backwards into a cradle, the core is flipped out of the cradle by the action of the web which is being unwound at a high rate of speed when it reaches the end of the roll. That danger is no longer present since the machine can operate only when the roll is placed properly in the cradle. Also, with the roll in the position shown in FIG. 9, the unwinding action will tend to drive the core downwardly rather than upwardly particularly when the end of the material is reached.

While the invention has been described with particular reference to the illustrated embodiments it will be understood that numerous modifications thereto will appcar to those skilled in the art. Also it will be understood that the above description and accompanying drawings should be taken as illustrative of the invention and not in a limiting sense.

Having thus described my invention, what I claim and desire to obtain by Letters Patent of the United States 1. A method for trimming relatively long threads attached at one end to a woven web, comprising the steps of (A) moving said web in a direction lying in the plane of said web,

(B) brushing said threads generally lengthwise of the direction of web travel with the attached end leading the free end thereof,

(C) brushing said thread forwardly and outwardly of said web at a speed in excess of said Web and (D) severing said threads while said threads are directed in a direction generally normal to the plane of said web.

2. A method for trimming relatively long threads attached at one end to a woven web, comprising the steps of (A) moving said web in a direction lying in the plane of said web,

(B) brushing said threads to lie diagonally of the direction of web travel with the attached end leading the free end thereof,

(C) brushing said threads forwardly and outwardly of said web at a speed in excess of said web and (D) severing said threads while said threads are directed in a direction generally normal to the plane of said web.

3. A method for trimming relatively long threads attached at one end to a woven web, comprising the steps of (A) moving said web in a direction lying in the plane of said web,

(B) brushint said threads forwardly and outwardly of said web at a speed in excess of said Web, and,

(C) severing said threads while said threads are arranged in a direction generally normal to the plane of said web.

4. A method for trimming relatively long threads attached at one end to a woven Web, comprising the steps of (A) moving said web in a direction lying in the plane of said web,

(B) directing said threads rearwardly of the direction of web travel so that said threads are arranged with their attached ends leading their free ends,

(C) brushing said threads forwardly and outwardly of said web and (D) severing said threads while said threads are arranged in a direction generally normal to the plane of said web.

5. A method of trimming relatively long threads at- I tached at one end to one face of a woven web, comprising the steps of (a) moving said web longitudinally in one direction to and past a trimming station,

(b) picking up the free end of each of said threads adjacent to and forwardly of said station to a position generally normal to the plane of said web, and

(0) cutting said threads near their attached ends at said station on and transversely along a line extending across the web at said face while said threads are held in said position.

6. The method of claim 5 including the step of arranging said threads to lie against said face all in the same general direction prior to picking up said threads.

7. A method of trimming relatively long and randomly distributed threads attached at one end to a web, comprising the steps of (a) moving said web longitudinally past a cutting element extending in closely spaced relation over the surface of said web,

(b) picking up the free end of each of said threads prior to their reaching said cutting elements so that the threads are disposed generally normal to the plane of said web, and

(c) holding the picked up threads taut as the web moves under said cutting elements whereby the picked up threads will be severed near their attached ends.

References titted by the Examiner UNITED STATES PATENTS 1,993,102 3/35 Klugh 225103 2,429,944 10/47 Rayburn et al 225-4 2,559,366 7/51 Morris 225-103 3,103,304 9/63 Nawalanci 2254 ANDREW R. JUHASZ, Primary Examiner. 

1. A METHOD FOR TRIMMING RELATIVELY LONG THREADS ATTACHED AT ONE END TO AWOVEN WEB, COMPRISING THE STEPS OF (A) MOVING SAID WEB IN A DIRECTION LYING IN THE PLANE OF SAID WEBS, (B) BRUSHING SAID THREADS GENERALLY LENGTHWISE OF THE DIRECTION OF WEB TRAVEL WITH THE ATTACHED WEB LEACING THE FREE END THEREOF, (C) BRUSHING SAID THREADS FORWARDLY AND OUTWARDLY OF SAID WEB AT A SPEED IN EXCESS OF SAID WEB AND (D) SERVING SAID THREADS WHILE SAID THREADS ARE DIRECTED IN A DIRECTION GENERALLY NORMAL TO THE PLANE OF SAID WEB. 